The present invention is for a sprinkler system and a sprinkler head design, namely, a sprinkler system having one low pressure water feed line that serves a plurality of individually actuated and programed sprinkler heads. The individually programed and actuated sprinkler heads make it possible to deliver an accurate amount of water at a frequency desired for the specific type of plant being served by the individual sprinkler head.
One of the major problems with horticultural sprinkler systems using the presently available components is devising a system design that provides the appropriate amount of water with the proper frequency for all of the various plants in the area to be automatically sprinkled. Some plants need deep watering while others require shallow watering; others require that the foliage not be wet during sprinkling to minimize the development of various diseases and infestations, while other plants are immune to such infestations or require wetting of the foliage during watering; some plants require watering daily or on alternate days particularly in warm or hot weather, while others are drought tolerant and need watering only once or twice a month. Then there are those plants that require protection from frost in cold weather while others do not. And how do you deal with a tropical plant that requires heavy and frequent watering that is planted in close proximity to drought tolerant plants that only require sparse watering, or different soil types which occur throughout a large planted area? These are very serious problems that may not be solvable with the present sprinkler equipment and controls that are currently available once the landscaping has been established.
Due to problems such as those recited above, in today""s market one""s landscaping and sprinkler system are usually designed and installed simultaneously so that all of the plants served by each circuit of the sprinkler system have similar watering requirements. Thus, sprinkler systems that are currently in use today require multiple watering circuits and various types of sprinkler heads with various coverage patterns.
It would be desirable if there was a horticultural sprinkler system that had none of the drawbacks of those presently available, and particularly a system that can just as readily be installed in an established landscaped area as together with the installation of new landscaping. Even more desirable would be a sprinkler system that easily permitted the introduction or removal of plants throughout the landscaped area and corresponding reprogramming of sprinkler heads, or even the enlarging of the landscaped area. A system that provides unrestricted creativity in the selection and placement of types and species of plants would also be very desirable. In addition it would be desirable to have a sprinkler system that requires the least number of parts, particularly different types, styles and coverage pattern sprinkler heads, preferably a single style sprinkler head. The present invention meets all of these requirements.
The present invention presents a unique irrigation sprinkler system with a unique sprinkler head design; a unique method of defining the planted area to be served by the sprinkler head; a unique method for determining when that planted area needs to be watered; a unique way of providing even coverage throughout the planted area when being watered; the ability to use one sprinkler head to individually water multiple, non-overlapping planted areas; a unique way of addressing multiple sprinkler heads in the same sprinkler system; and a unique method for remotely determining the integrity of the sprinkler system.
Each sprinkler head of the present invention irrigation sprinkler system is disposed to be coupled to the same water feeder line to deliver water to a planted area of interest. Each sprinkler head of the present invention includes an input port disposed to be coupled to the water feeder line with a control value coupled to the input port to provide controlled water flow through the control valve to the interior of the sprinkler head. In addition there is a flow rate monitoring unit adjacent the control value to monitor the water flow rate as it exits the control valve for delivery to a nozzle with a proximate end adjacent the flow rate monitoring unit to receive the water flow from the control valve and to expel the water from the distal end of the nozzle to the planted area of interest. The sprinkler head further includes a drive means affixed to the nozzle for angularly positioning the distal end of the nozzle, and an angular position monitoring unit to determine the position of the drive means. To control the operation of the various components of the sprinkler head, there is also a sprinkler head control subsystem coupled to the control valve, the flow rate monitoring unit, the drive means and the angular position monitoring unit to monitor and control the water flow rate through, and the angular position of, the nozzle to deliver water to the planted area of interest.
One embodiment of the flow rate monitoring unit could include a flexible finger having a proximate end mounted to a fixed position relative to the water flow and a distal end extending into the path of the water flow. In this embodiment, the distal end of the flexible finger is in a relaxed position when the water flow rate is zero and a displaced position when the water flow rate is non-zero, with the extent of the displaced position being directly related to the water flow rate. Additionally there is a magnet mounted at either a fixed position adjacent the distal end of the flexible finger or on the distal end of the flexible finger. Working in cooperation with the magnet, there is a flow rate magnetic field sensor at the other position adjacent the magnet to provide an electrical signal that is directly related to the strength of the magnetic field detected from the magnet. The strength of that detected magnetic field in turn is strongest when the water flow rate is zero and of decreasing strength the greater the water flow rate, i.e., the signal strength is greatest when the magnet is closest to flow rate magnetic sensor with the signal strength deceasing the further apart the magnet and the flow rate magnetic sensor are from each other.
An embodiment of the angular position monitoring unit similarly includes a magnet mounted at either a fixed position adjacent the drive means or on the drive means. The corresponding angular position magnetic field sensor is then mounted at the other location with the angular position magnetic field sensor providing the strongest electrical signal when the magnet is adjacent the angular position magnetic field sensor to define the zero degree angular position for the nozzle. The zero position is then determined before the control subsystem causes the drive means to operate between selected angular positions in the delivery of water to the planted area of interest.
The overall sprinkler system of the present invention, as stated above, provides water from a water source to the planted area of interest, with the sprinkler system including a water feeder line disposed to be coupled to the water source which could provide water from a marginal water pressure, perhaps as low as 20 psi (pounds per square inch) or normal city water system pressures in the range of 60 to 90 psi, or at even higher pressures. Coupled to that water feeder line is at least one a sprinkler head of the type discussed above, or equivalent to that sprinkler head. Additionally, each sprinkler head is individually electrically controllable during the watering cycle to continuously vary the angular position of, and the water flow rate through, the nozzle to the planted area of interest to provide even coverage of that area. The overall system also includes a power and data line coupled to each of the sprinkler heads to provide power and control data to each one from a master controller disposed to be connected to a power source and coupled to the power and data line to provide power and control data to the sprinkler heads and other elements of the system.
In sprinkler system of the present invention each sprinkler head can be individually programed either from the master controller or remotely with a programing unit that plugs into the sprinkler head that is to be programed. Two embodiments are included to accomplish that programing. In the first embodiment, an optional remote programing unit is provided. In the second embodiment, the master controller is divided into a power hub and a detachable programing unit that is plugged into the power hub when not in use remotely at one of the sprinkler heads. In the first of these embodiments, both the master controller and the remote programing unit includes a display and keyboard for the user to program each sprinkler head. Whereas in the second embodiment, the keyboard and display are only included in the detachable programming unit which is possible since the keyboard and display are only needed at one or the other location when a sprinkler head is being programed. The display and keyboard are also useful at the master controller location when in normal operation of the sprinkler system for displaying time or status of the system or for use by the user to inquire about various functions and status of the system.
Additionally there is an optional weather station coupled to the power and data line to provide weather related data to the master controller. That data might include temperature, humidity, wind direction and strength, etc.
Another element of the present invention is a method of watering a contiguous planted area of interest with a processor controlled automatic sprinkler head as described above connected to a water line with that water being delivered through the nozzle. That is accomplished by selectively oscillating the particular sprinkler head from side to side to direct the water stream from the nozzle from side to side within the planted area of interest under control of the processor. In coordination with the back and fourth oscillation of the nozzle, the water flow rate through the nozzle is selectively varied to direct the water from the nozzle at varying distances from the nozzle within the planted area of interest. Alternately, the flow rate through the sprinkler head could be varied to direct the water stream in and out (closer and farther) from the sprinkler head while coordinating the angular position of the sprinkler head to direct the water stream throughout the planted area of interest. Using either of these techniques, water is directed to the planted area of interest in a in a zig-zag fashion to cover the entire planted area of interest.
The method of programing each sprinkler head for delivery of water to a planted area of interest is also unique, as is the method of determining when and how much water to deliver to the planted area of interest. First, the area of interest must be determined and programed into the corresponding sprinkler head. Typically the shape of that area will be a point, a line, a triangle or a multi-sided polygon in which case, one, two, three or more points, respectively, with corresponding electronic signal values that define the point, ends or corners of the area of interest must be programed into the sprinkler head. For each point, a value corresponding to an electrical signal to positions the nozzle at the angular position where the water from the nozzle is in the direction of the point, and a value corresponding to the electrical signal to control the flow rate through the nozzle to direct the water the necessary distance from the sprinkler head to the point, are stored in local memory in the sprinkler head. The values of the necessary angular and distance positions are determined by the use, either with the master controller or with a unit remotely at the sprinkler head first initiates water flow from the nozzle, and then using the keyboard adjusts the angular position of, and the water flow rate from, the nozzle until the stream of water hits the point in question. In each case, a save function is initiated to save values that define the point such that the local processor of the sprinkler head can repeatedly direct a water stream to it. Once all of the values for necessary points to define the area of interest are entered, the local processor is prepared to deflect the stream of water from the nozzle throughout the area of interest at the single point, along the line defined by two points, or within the line segments that connect to points at the three or more corners, when the master controller instructs the local processor to proceed. That being done, the water flow is stopped until the master controller instructs that it be restarted.
Another unique feature of the present invention is the determination of how much water to deliver to the planted area of interest when the local processor of the sprinkler head is instructed by the master controller to water that area. Also during the programing of the area of interest into the sprinkler head, the dose (number of inches) of water that is to be delivered in a single watering cycle is input to memory along with the corner definitions. Then, using the corner definitions, the area (number of square feet) of the planted area of interest is calculated by the local processor. Then, knowing that area, the dose and the nominal flow rate through the nozzle for the various points, the local processor calculates the length of time needed to evenly deliver the desired dose throughout the planted area of interest. That time is then also stored in memory in the sprinkler head.
If the planted area of interest is a single point, then a nominal area is used as the area of the planted area of interest for the watering duration calculation. Similarly, if the planted area of interest is a line, then the area of the planted area of interest is calculated by multiplying the distance between to the two points the define the ends of the line by a nominal width for the duration calculation.
Then to get even coverage throughout the planted area of interest the stream of water is varied throughout the area by a technique such as zig-zagging the stream of water.
The method for determining when each area of interest needs to be watered also requires that two additional pieces of data be known: a stress tolerance level in inches of water (the number of inches of water loss that a plant can withstand before experiencing damage) for the plants in the area of interest, and a typical value of the evapotransporation rate (ET0) in the geographic area where the planted area is located. That stress tolerance level is entered and saved in the sprinkler head by the user when programing for dose and the points that define the area of interest. Since ET0 is dependent on the weather in the geographic area where the sprinkler system is located, the same ET0 is used for calculating when watering is needed by all of the planted areas of interest served by the sprinkler system, thus ET0 is preprogramed into the master controller, or is determined by the master controller as needed.
With those values being available, it is possible to determine at any particular time whether each planted area of interest being served by the sprinkler system needs to be watered. This is done by the master controller sending each sprinkler head attached to the sprinkler system the ET0 for that point in time to be used in the calculation to determine if watering is needed. Each local processor of each sprinkler head then subtracts the ET0 value either from the programed stress tolerance level or the results of a previous one of these calculations which has been stored as the effective stress value. The resulting effective stress value is then updated in memory to the value just calculated. Next the local processor determines if the effective stress value is zero or a negative value. If so, the corresponding area of interest requires watering for the period of time determined based on the square footage of that area and other values.
The next step in the watering process is for each local processor to communicate the number of minutes that are required by that sprinkler head to water those areas that have reached the zero or negative threshold. Knowing the number of sprinkler heads that need to water and the length of time need by each, the master controller calculates the maximum number of sprinkler heads that can be active at the same time using the information provided by the sprinkler heads and knowing the available water pressure of the water line. Next the master controller prepares a sequence of steps for activating the ready sprinkler heads with no more than the determined maximum number sprinkler heads in each step of the sequence using the maximum number and the individual watering cycle durations needed by the sprinkler heads that are ready to water. Then the master controller communicates individually with each sprinkler head at the beginning of each sequence step in which that sprinkler head has been included to commence watering for a predetermined period of time until all sequence steps have been completed. Then when each sprinkler head has completed watering, for those areas of interest that have just been watered, resets the stored effective stress value to the stress tolerance level programed into the sprinkler head by the user.
Another feature of the present invention is a technique for determining the integrity of the automatic sprinkler system at any time. To do so, each local processor is programed to report to the master controller: an inability to water an area when authorized to do so by said master controller; and when there is water flow through the corresponding sprinkler head at a time when unauthorized to initiate water flow. Additionally, the master controller individually interrogates each local processor in each sprinkler head at will to request an acknowledgment from each local processor as being on-line. From the information provided by the local processor, or processors, by the lack of a response to the individual interrogations, the master controller is able to identify a possible problem and the sprinkler head where that problem is located.